Method of preparing a treated article and treated article formed therefrom

ABSTRACT

A method of preparing a treated article comprises the step of providing a slurry comprising fibers. The method further comprises the step of combining the slurry and a first fluorinated composition to form a mixture. In addition, the method comprises the step of forming at least one sheet from the mixture. Finally, the method comprises the step of applying a second fluorinated composition on at least one surface of the at least one sheet to prepare the treated article.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of Ser. No. 14/304,597 filed on Jun.13, 2014, now U.S. Pat. No. 9,133,584, which is a continuation of Ser.No. 13/351,286 filed on Jan. 17, 2012, now U.S. Pat. No. 8,771,470.

FIELD OF THE INVENTION

The present invention generally relates to a method of preparing atreated article and, more specifically, to a method of preparing atreated article having excellent resistance to oil and water.

DESCRIPTION OF THE RELATED ART

Various methods of treating articles are known in the art and aregenerally tailored based on the particular end use of the articles. Forexample, in certain industries, such as the textile industry, textilearticles are treated to impart the textile articles with desirablephysical properties, such as resistance to oil and/or water. One textilearticle that is commonly treated for purposes of imparting the textilearticle with such properties is paper. For example, treated paper isutilized in the fast food industry to prevent oil and grease frompermeating the packaging of food items, e.g. fried foods. Fluoropolymersare typically utilized when preparing treated textile articles to impartthe treated textile articles with resistance to oil and/or water.

SUMMARY OF THE INVENTION

The present invention provides a method of preparing a treated article.The method comprises the step of providing a slurry comprising fibers.The method further comprises the step of combining the slurry and afirst fluorinated composition to form a mixture. In addition, the methodcomprises the step of forming at least one sheet from the mixture.Finally, the method comprises the step of applying a second fluorinatedcomposition on at least one surface of the at least one sheet to preparethe treated article.

The method of the present invention prepares treated articles havingexcellent physical properties, including resistance to oil and water,even when such treated articles are creased or otherwise deformed. Forexample, conventional treated articles typically have desirableresistance to creasing yet have undesirable surface performance, orconventional treated articles have desirable surface performance whichsuffers considerably when the treated articles are creased or otherwisebent/deformed. However, the method of the present invention preparestreated articles having both excellent surface performance andresistance to creasing. Additionally, the method of the presentinvention utilizes the first and second fluorinated compositions, whichhas a synergistic effect, thereby reducing costs and volume relative tomethods utilizing conventional fluorinated compositions.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides a method of preparing a treated article.The method of the present invention prepares treated articles havingexcellent physical properties, including oil and water repellency, asdescribed in greater detail below. The method of the present inventionis particularly suitable for preparing treated paper; however, it is tobe appreciated that the method is not limited to such articles. Forexample, the method may be utilized to prepare other articles comprisingfibers, such as natural and/or synthetic textiles.

The method comprises the step of providing a slurry comprising fibers.The slurry may be provided in any suitable manner. For example, theslurry may be prepared, obtained, purchased, etc. The fibers of theslurry may comprise natural fibers, synthetic fibers, semi-syntheticfibers, inorganic fibers, and combinations thereof. Specific examples ofnatural fibers include those derived from plant or wood matter, whichmay also be referred to as cellulosic fibers, such as bamboo fibers,bent grass fibers, sawgrass fibers, bagasse fibers, straw fibers, hayfibers, spruce fibers, pine fibers, fir fibers, larch fibers, eucalyptusfibers, aspen fibers, birch fibers, etc. When the natural fibers arederived from wood matter, the wood matter may be softwood and/orhardwood. Other examples of natural fibers include cotton, hemp, wool,silk, etc. Specific examples of synthetic fibers include polyamidefibers, polyester fibers, polyvinyl alcohol fibers, polyacrylonitrilefibers, polyvinyl chloride fibers, polypropylene fibers, etc. Specificexamples of semi-synthetic fibers include rayon, acetate, etc. Specificexamples of inorganic fibers include glass fibers, carbon fibers,asbestos fibers, etc. In certain embodiments, the fibers of the slurrycomprise natural fibers, such as cellulosic fibers.

When the step of providing the slurry comprises preparing the slurry,the slurry may be prepared in accordance with methods generally known inthe art. For example, in embodiments in which the fibers comprisecellulosic fibers, the slurry may be prepared by mechanical pulpingprocesses; thermomechanical pulping processes; chemithermomechanicalpulping processes; chemical pulping processes, such as Kraft processes,Sulfite processes, and Soda processes; recycled pulping processes;organosolv pulping processes; etc. Alternatively, the slurry may beprepared by purchasing or otherwise obtaining dried cellulosic fibers,which are generally referred to in the art as “market pulp.” In theseembodiments, the market pulp is generally reconstituted into water,which is referred to as hydropulping. The fibers may be bleached,contingent upon the desired appearance of the treated article. Whenbleached, the fibers may be bleached with, for example, chlorine,chlorine dioxide, oxygen, ozone, hydrogen peroxide, etc.

Typically, the fibers are present in the slurry in an amount of fromgreater than 0 to 5, alternatively from 0.5 to 3.75, alternatively from1.0 to 2.5 percent by weight based on the total weight of the slurry. Ofcourse, it is to be appreciated that the fibers may be present in theslurry in amounts other than those set forth above contingent on thepresence or absence of various optional components, as described ingreater detail below. The balance of the slurry typically compriseswater or a combination of water and a water-soluble solvent, asdescribed in greater detail below.

In certain embodiments in which the fibers comprise cellulosic fibers,the fibers of the slurry are typically refined. Typically, the fibers ofthe slurry are refined by subjecting the slurry to shear forces, whichseparate cellulosic masses or fiber clusters into individual fibers.Generally, the fibers of the slurry are not refined until the slurry isprepared or provided, i.e., “market pulp” is typically not refined untilit has been reconstituted into water to form the slurry.

The method further comprises the step of combining the slurry and afirst fluorinated composition to form a mixture. Most typically, thefirst fluorinated composition is further defined as an anionicfluorinated composition. However, in other embodiments, the firstfluorinated composition is further defined as a cationic fluorinatedcomposition.

In certain embodiments in which the first fluorinated composition is theanionic fluorinated composition, the first fluorinated compositioncomprises a first fluorinated copolymer. The first fluorinated polymertypically comprises from 40 to 98 mass % of polymerized units (a′) basedon monomer (a), from 1 to 50 mass % of polymerized units (b′) based onmonomer (b) and from 1 to 10 mass % of polymerized units (c′) based onmonomer (c). Monomers (a), (b) and (c) are described in greater detailbelow with reference to the first fluorinated polymer of the firstfluorinated composition. In addition, this specific example of the firstfluorinated polymer is described in U.S. Publ. Pat. Appln. No.2010/0168319, which is incorporated by reference herein in its entirety.

Monomer (a), which is utilized to form the first fluorinated polymer,comprises a compound represented by (Z—Y)_(a)X, wherein Z is a C₁₋₆perfluoroalkyl group or a monovalent group represented byC_(b)F_(2b+1)O(CFWCF₂O)_(c)CFK—, wherein b is an integer of from 1 to 6,c is an integer of from 1 to 4, and each of W and K which areindependent of each other, is a fluorine atom or a trifluoromethylgroup, Y is a single bond or a bivalent organic group containing nofluorine atom, a is 1 or 2, provided that when a is 1, X is —CR═CH₂,—COOCR═CH₂, —OCOCR═CH₂, —OCH₂-φ-CR═CH₂ or —OCH═CH₂, and when a is 2, Xis —CH[—(CH₂)_(d)CR═CH₂]—, —CH[—(CH₂)_(d)COOCR═CH₂]—,—CH[—CH₂)_(d)OCOCR═CH₂]— or —OCOCH═CHCOO—, R is a hydrogen atom, amethyl group or a halogen atom, p is a phenylene group, d is an integerof from 0 to 4, and when a is 2, two (Z—Y) present in one molecule maybe the same or different from each other.

Monomer (b), which is utilized to form the first fluorinated polymer,comprises a compound represented by CH₂═CR¹-G-(R²O)_(e)—R³, wherein R¹is a hydrogen atom or a methyl group, R² is a C₂₋₄ alkylene group, or aC₂₋₃ alkylene group having some or all of its hydrogen atoms substitutedby hydroxyl groups, e is an integer of from 1 to 10, G is —COO(CH₂)_(f)—or —COO(CH₂)_(g)—NHCOO—, wherein f is an integer of from 0 to 4, and gis an integer of from 1 to 4, and R³ is a hydrogen atom, a methyl group,an acryloyl group, a methacryloyl group or an allyl group.

Finally, monomer (c), which is also utilized to form the firstfluorinated polymer, comprises a compound represented byCH₂═C(COOH)-Q-COOH, wherein Q is a C₁₋₄ alkylene group, or a C₂₋₃alkylene group having some or all of its hydrogen atoms substituted byhydroxyl groups, and in the monomer (c), some or all of the carboxylgroups may form at least one salt selected from an ammonium salt and anorganic amine salt.

Alternatively, in embodiments in which the first fluorinated compositionis the anionic fluorinated composition, the first fluorinatedcomposition comprises a second fluorinated copolymer. One specificexample of the second fluorinated polymer is described in International(PCT) Publication No. WO2011/027877, which is incorporated by referenceherein in its entirety. The second fluorinated polymer described inInternational (PCT) Publication No. WO2011/027877 is set forth ingreater detail below.

In particular, in certain embodiments, the second fluorinated polymercomprises repeating units derived from: (a) a fluorine-containingmonomer having a fluoroalkyl group represented by the general formula:CH₂═C(—X′)—C(═O)—Y′—Z′—Rfwherein X′ represents a hydrogen atom, a linear or branched C₁ to C₂₁alkyl group, a halogen atom, a CFX¹X² group wherein X¹ and X² are ahydrogen atom, a halogen atom, a cyano group, a linear or branchedC₁-C₂₁ fluoroalkyl group, a substituted or non-substituted benzyl group,or a substituted or non-substituted phenyl group; Y′ is —O— or —NH—; Z′is a C₁-C₁₀ aliphatic group, a C₆-C₁₀ aromatic or cyclic aliphaticgroup, a —CH₂CH₂N(R⁴)SO₂— group wherein R⁴ is a C₁-C₄ alkyl group, a—CH₂CH(OZ¹)CH₂— group wherein Z¹ is a hydrogen atom or an acetyl group,a —(CH₂)_(h)—SO₂—(CH₂)_(i)— group or a —(CH₂)_(h)—S—(CH₂)_(i)— groupwherein h is 1-10 and i is 0-10; and Rf is a C₁-C₆ linear or branchedfluoroalkyl group; (b) a hydrophilic monomer, and (c) a monomer havingan anion-donating group. The second fluorinated copolymer typically hasa weight average molecular weight of 100,000 or more. Specific examplesof (a), (b) and (c) are provided in International (PCT) Publication No.WO2011/027877.

As introduced above, in various embodiments, the first fluorinatedcomposition is a cationic fluorinated composition. In certainembodiments in which the first fluorinated composition is the cationicfluorinated composition, the first fluorinated composition comprises athird fluorinated copolymer. One specific example of the thirdfluorinated copolymer is described in U.S. Pat. No. 6,933,338, which isincorporated by reference herein in its entirety.

The third fluorinated copolymer typically comprises (1) a monomer unitbased on a (meth)acrylate having a polyfluoroalkyl group; (2) a monomerunit based on an alkyl(meth)acrylate having a C₁₆-C₁₂ alkyl group; (3) amonomer unit based on an alkyl(meth)acrylate having a C₁-C₂₂ alkylgroup; and (4) a monomer unit based on at least one compound selectedfrom the group consisting of 2-isocyanate ethyl methacrylate,1,3,3-trimethyl-4-isocyanate cyclohexylmethylamidoxyethyl methacrylateof general formula 1 below and 1,3,3-trimethyl-4-isocyanatecyclohexylmethylamidoxyethyl acrylate of general formula 2 below, theisocyanate group of which is blocked. General formula 1 is as follows:

an general formula 2 is

Specific examples of monomer units (1)-(4) are described in U.S. Pat.No. 6,933,338.

Alternatively, in embodiments in which the first fluorinated compositionis the cationic fluorinated composition, the first fluorinatedcomposition comprises a fourth fluorinated copolymer. One specificexample of the fourth fluorinated copolymer is disclosed in U.S. Pat.No. 7,485,688, which is incorporated by reference herein in itsentirety.

In certain embodiments, the fourth fluorinated copolymer comprises 60 to98 mass % of polymerized units (d)′ based on monomer (d), from 1 to 20mass % of polymerized units (e)′ based on monomer (e) and from 1 to 30mass % of polymerized units (f)′ based on monomer (f), which are eachdescribed in greater detail below.

In particular, monomer (d), which is utilized to form the fourthfluorinated copolymer, comprises a compound represented by(Z″—Y″)_(j)X″, wherein Z″ is a C₁₋₆ perfluoroalkyl group or a grouprepresented by C_(k)F_(2k+1)O(CFW′CF₂O)_(l)CFK′—, wherein k is aninteger of from 1 to 6, l is an integer of from 1 to 4, and each of W′and K′ is independently a fluorine atom or —CF₃, Y″ is a bivalentorganic group or a single bond, j is 1 or 2, and X″ is a polymerizableunsaturated group provided that when j is 1, X″ is —CR⁵═CH₂,—COOCR⁵═CH₂, —OCOCR⁵═CH₂, —OCH₂-φ-CR⁵═CH₂ or OCH═CH₂, and when j is 2,X″ is ═CH(CH₂)_(m)CR⁵═CH₂, ═CH(CH₂)_(m)COOCR⁵═CH₂,═CH(CH₂)_(m)OCOCR⁵═CH₂ or —OCOCH═CHCOO—, wherein R⁵ is a hydrogen atom,a methyl group or a halogen atom, φ is a phenylene group, and m is aninteger of from 0 to 4.

Monomer (e), which is utilized to form the fourth fluorinated copolymer,comprises a compound represented by CH₂═CR⁶-G′-(R⁷O)_(n)—R⁸, wherein R⁶is a hydrogen atom or a methyl group, R⁷ is a C₂₋₄ alkylene group or anotherwise C₂₋₃ alkylene group in which some or all of the hydrogen atomshave been replaced by hydroxyl groups, n is an integer of from 1 to 50,G′ is —COO(CH₂)_(o)— or —COO(CH₂)_(s)—NHCOO—, wherein o is an integer offrom 0 to 4, and s is an integer of from 1 to 4, and R⁸ is at least oneof an acryloyl group and a methacryloyl group.

Finally, monomer (f), which is utilized to form the fourth fluorinatedcopolymer, comprises a compound represented by CH₂═CR⁹-M-Q′-NR¹⁰R¹¹ orCH₂═CR⁹-M-Q′-N(O)R¹⁰R¹¹, wherein R⁹ is a hydrogen atom or a methylgroup, M is —COO— or —CONH—, Q′ is a C₂₋₄ alkylene group or an otherwiseC₂₋₃ alkylene group in which some or all of the hydrogen atoms have beenreplaced by hydroxyl groups, and each of R¹⁰ and R¹¹ comprises a benzylgroup, a C₁₋₈ alkyl group or an otherwise C₂₋₃ alkylene group in whichsome of the hydrogen atoms have been replaced by hydroxyl groups, or R¹⁰and R¹¹ may form a morpholino group, a piperidino group or apyrrolidinyl group, together with a nitrogen atom.

When the first fluorinated composition is the anionic fluorinatedcomposition, the first fluorinated composition may comprise one or morefluorinated polymers other than or in addition to the first fluorinatedpolymer or the second fluorinated polymer. Similarly, the firstfluorinated composition may comprise a combination of the first andsecond fluorinated polymers, and may further comprise additionalfluorinated polymers. Typically, when the first fluorinated compositionis anionic, the anionicity of the first fluorinated composition isderived from the particular fluorinated polymer utilized. Accordingly,the particular fluorinated polymer utilized (e.g. the first and/orsecond fluorinated polymers) is generally anionic.

In alternative embodiments in which the first fluorinated composition isthe cationic fluorinated composition, the first fluorinated compositionmay comprise one or more fluorinated polymers other than or in additionto the third fluorinated polymer or the fourth fluorinated polymer.Similarly, the first fluorinated composition may comprise a combinationof the third and fourth fluorinated polymers, and may further compriseadditional fluorinated polymers. Typically, when the first fluorinatedcomposition is cationic, the cationicity of the first fluorinatedcomposition is derived from the particular fluorinated polymer utilized.Accordingly, the particular fluorinated polymer utilized (e.g. the thirdand/or fourth fluorinated polymers) is generally cationic.

Because the first fluorinated composition may comprise any of the first,second, third, and/or fourth fluorinated copolymers, or fluorinatedpolymers other than or in addition to the first, second, third, and/orfourth fluorinated copolymers, the particular fluorinated polymer(s)employed in the first fluorinated composition is merely referred toherein as “the fluorinated polymer of the first fluorinated composition”for purposes of brevity and clarity. It is to be appreciated that theterminology “the fluorinated polymer of the first fluorinatedcomposition” encompasses any combination of the first, second, third,and/or fourth fluorinated copolymers, as well as fluorinated polymersother than or in addition to the first, second, third, and/or fourthfluorinated copolymers.

The first fluorinated composition is typically a dispersion of thefluorinated polymer in an aqueous medium. The fluorinated polymergenerally has a particle size of at most 100 nm, alternatively at most50 nm, alternatively at most 10 nm, while dispersed in the aqueousmedium.

The aqueous medium of the first fluorinated composition is typicallywater or a combination of water and a water-soluble solvent. Specificexamples of the water-soluble solvent include at least one solventselected from the group of propylene glycol, dipropylene glycol,tripropylene glycol, propylene glycol monomethyl ether, propylene glycolmonoethyl ether, dipropylene glyocol monomethyl ether, dipropyleneglycol monoether ether, tripropylene glycol monomethyl ether, diacetonealcohol, and combinations thereof. Most typically, the aqueous medium ofthe first fluorinated composition comprises water or a combination ofwater and at least one water-soluble solvent selected from the group ofpropylene glycol, dipropylene glycol and tripropylene glycol. When theaqueous medium of the first fluorinated composition comprises thecombination of water and the water-soluble solvent, the water and thewater-soluble solvent are typically present in the aqueous medium in aratio of 99:1 to 15:85 parts by weight water to parts by weightwater-soluble solvent. Most typically, the water-soluble solvent ispresent in an amount of less than 20 parts by weight relative to 100parts by weight of water and the water-soluble solvent.

The aqueous medium of the first fluorinated composition may comprise avolatile organic solvent. However, the volatile organic solvent of theaqueous medium is generally present in the aqueous medium of the firstfluorinated composition in an amount of less than 1.0, alternativelyless than 0.5, alternatively less than 0.1, alternatively 0.0 percent byweight based on the total weight of the aqueous medium. As understood inthe art, a volatile organic solvent is an organic solvent whichvolatilizes when stored at room temperature. More specifically, avolatile organic solvent is an organic solvent having a boiling point ofat most 100° C. It is to be appreciated that a solvent which forms anazeotropic mixture with water is not included within the definition ofvolatile organic solvent as utilized herein.

The first fluorinated composition may further comprise components inaddition to the fluorinated polymer described above. For example, thefirst fluorinated composition may further comprise a starch, a resin, acrosslinking agent, a catalyst, an inorganic or organic filler, acoagulant, a supporting agent (e.g. dextrin), a holding agent, aflocculant, a buffering agent, a bactericide, a biocide, a metalion-sealing agent, a hydrophobizing agent (e.g. alkenyl succinicanhydride and/or alkyl ketene dimer), and the like, as well as variouscombinations of such components.

Specific examples starches suitable for the first fluorinatedcomposition include, but are not limited to, a hydroxyethylated starch,a cationic starch, an amphoteric starch, an oxidized starch, aphosphorylated starch, an enzyme-modified starch, and combinationsthereof.

Specific examples of resins suitable for the purposes of the firstfluorinated composition include, but are not limited to, a polyvinylalcohol, a polyvinyl chloride latex, a polyvinyl alcohol, apolyamideamine epichlorohydrin-modified resin, anN-vinylformaldehyde-vinylamine copolymer, and combinations thereof.

Specific examples of crosslinking agents suitable for the purposes ofthe first fluorinated composition include, but are not limited to, acondensate or precondensate of urea or melamine-formaldehyde,methylol-dihydroxyethylene-urea or a derivative thereof, urone,methylol-ethylene-urea, methylol-propylene-urea, methylol-triazone, adicyandiamide-formaldehyde condensate, methylol carbamate,methylol(meth)acrylamide, a polymer thereof, divinyl sulfone, polyamideor a cationic derivative thereof, an epoxy derivative such as glycidylglycerol, a halide derivative such as(epoxy-2,3-propyl)trimethylammonium chloride orN-methyl-N-(epoxy-2,3-propyl)morpholinium chloride, a pyridinium salt ofethylene glycol chloromethyl ether, and combinations thereof.

Specific examples of catalysts suitable for the purposes of the firstfluorinated composition include, but are not limited to, ammoniumchloride, an alkanolamine salt, a zirconium acetate salt, andcombinations thereof.

Specific examples of fillers inorganic and organic fillers includesilica, alumina, sericin, resin powder, talc, kaolin, precipitatedcalcium carbonate, ground calcium carbonate, bentonite, clays, titaniumdioxide, and the like. Such fillers may optionally be utilized in acarrier medium.

The particular components present in the first fluorinated composition,as well as their respective amounts, may very dependent upon theparticular fibers employed in the slurry, as well as the desired end useof the treated article formed from the first fluorinated composition. Ifpresent, the starch is typically utilized in the first fluorinatedcomposition in an amount to provide from 0.001 to 10, alternatively from0.005 to 8, alternatively from 0.01 to 6 percent by weight based on thetotal dry weight of the fibers of the slurry. The fluorinated polymer ofthe first fluorinated composition is typically present in the firstfluorinated composition in an amount to provide from 0.001 to 3.5,alternatively from 0.005 to 2.5, alternatively 0.01 to 1.5 percent byweight of the fluorinated polymer based on the total dry weight of thefibers in the slurry.

The slurry and the first fluorinated composition may be combined to formthe mixture according to various methods. For example, the firstfluorinated composition may be added to the slurry in a vessel, or theslurry may be added to the first fluorinated composition in a vessel.Alternatively, both the first fluorinated composition and the slurry maybe disposed in a vessel contemporaneously. It is to be appreciated thatthe first fluorinated composition may be formed prior to combining thefirst fluorinated composition and the slurry, or the individualcomponents or combinations of the individual components of the firstfluorinated composition may be individually or discretely combined withthe slurry such that the first fluorinated composition is formed in theslurry. Typically, the mixture formed from combining the firstfluorinated composition and the slurry is mixed or otherwise blended.

In various embodiments, the mixture is diluted to provide a desiredfinal consistency. Typically, the mixture is diluted such that thefibers are present in the mixture in an amount of from 0.001 to 4.0,alternatively from 0.005 to 3.0, alternatively from 0.01 to 2.0 percentby weight based on the dry weight of the fibers and the total weight ofthe mixture. It is to be appreciated that the slurry may optionally bediluted prior to forming the mixture instead of or in addition todiluting the mixture. If desired, an additional amount of the firstfluorinated composition, or an additional amount of the fluorinatedpolymer of the first fluorinated composition, may be combined with themixture once diluted.

The method of the present invention further comprises the step offorming at least one sheet from the mixture. For purposes of clarity,the at least one sheet is referred to herein merely as “the sheet,”which is to be understood to encompass even a plurality of sheets. Inembodiments where the fibers comprise cellulosic fibers such that thetreated article is treated paper, the sheet ultimately becomes paper.Methods of forming sheets are well known in the art. For example, thesheet is typically formed on a metal substrate, such as stainless steel,or what is referred to in the art as monofilament wire. The relativedimensions (e.g. thickness, length, width) of the sheet may varycontingent on a variety of factors, such as the desired end use of thetreated article formed via the method.

The sheet is typically dried once formed from the mixture to removeexcess water and/or water-soluble solvent therefrom. The sheet may bedried via vacuum and/or foil dewatering. Alternatively, the sheet may bedried via press dewatering, in which a pressure is applied to the sheet.The pressure utilized when the sheet is dried via press dewatering istypically from 0.5 to 200 psig. Further, the sheet may be dried viacontract dewatering, in which the sheet is dried via exposure topapermachine clothing, which absorbs excess water and/or thewater-soluble solvent from the sheet. In addition, the sheet may bedried via contract drying, in which the sheet is in contact with metalrollers having a smooth surface. The metal rollers utilized in contractdrying are typically heated, e.g. from 150 to 280° F. Any combination ofthese methods, or additional methods of drying the sheet to removeexcess water and/or water-soluble solvent which are known in the art,may be employed. In certain embodiments, all of the methods of dryingthe sheet described above are employed, typically in the order in whichthey are introduced above.

The method further comprises the step of applying a second fluorinatedcomposition on at least one surface of the sheet to prepare the treatedarticle. In various embodiments, the second fluorinated composition isapplied on two or more surfaces of the sheet. For example, mosttypically, the second fluorinated composition is applied on all majorsurfaces of the sheet. These major surfaces of the sheet are generally atop and a bottom surface, depending on the relative orientation of thesheet. When the treated article is the treated paper, the major surfacesof the sheet are those having the greatest surface area.

The step of applying the second fluorinated composition on at least onesurface of the sheet is not particularly limited so long as it capableof contacting the second fluorinated composition and the sheet. Forexample, the second fluorinated composition may be applied on at leastone surface of the sheet by spraying, brushing, padding, size presscoating, metering size press coating, film press coating, gravurecoating, flexo coating, roller coating, rotor dampening, foaming, gateroll coating, bill blade coating, bar coating, intaglio coating, reverseroll coating, skid roll coating, transfer (offset) roll coating, knifecoating, knife-over-roll coating, J-coating, air knife coating, curtaincoating, and combinations thereof.

The second fluorinated composition may be the same as or different fromthe first fluorinated composition. In certain embodiments, the secondfluorinated composition and the first fluorinated composition are thesame. In other embodiments, the second fluorinated composition and thefirst fluorinated composition are different.

In particular, both the first and second fluorinated compositions may beanionic fluorinated compositions, or both the first and secondfluorinated compositions may be cationic fluorinated compositions. Whenthe first and second fluorinated compositions are both anionicfluorinated compositions or are both cationic fluorinated compositions,both the first and second fluorinated compositions may comprise the samecomponents in the same relative amounts, or may comprise the samecomponents in different relative amounts, or different componentsaltogether. For example, when the first and second fluorinatedcompositions are both anionic fluorinated compositions, both the firstand second fluorinated compositions may comprise the first fluorinatedcopolymer (or the second fluorinated copolymer), or the firstfluorinated composition may comprise the first fluorinated copolymer andthe second fluorinated composition comprises the second fluorinatedcopolymer, or vice versa. Similarly, when the first and secondfluorinated compositions are both cationic fluorinated compositions,both the first and second fluorinated compositions may comprise thethird fluorinated copolymer (or the forth fluorinated copolymer), or thefirst fluorinated composition may comprise the third fluorinatedcopolymer and the second fluorinated composition comprises the fourthfluorinated copolymer, or vice versa.

Similarly, the second fluorinated composition may comprise any of theadditional components described above relative to the first fluorinatedcomposition. For example, the second fluorinated composition may furthercomprise a starch, a resin, a crosslinking agent, a catalyst, aninorganic or organic filler, a coagulant, a supporting agent (e.g.dextrin), a holding agent, a flocculant, a buffering agent, abactericide, a biocide, a metal ion-sealing agent, a hydrophobizingagent (e.g. alkenyl succinic anhydride and/or alkyl ketene dimer), andthe like, as well as various combinations of such components. Specificexamples of these components are set forth above with respect to thefirst fluorinated composition.

Like the first fluorinated composition, the second fluorinatedcomposition is typically a dispersion of the fluorinated polymer in anaqueous medium. The aqueous medium of the second fluorinated compositionis typically water or a combination of water and a water-solublesolvent, as described above relative to the first fluorinatedcomposition.

The second fluorinated composition typically comprises the particularfluorinated copolymer in an amount similar to that employed in the firstfluorinated composition. For example, when the second fluorinatedcomposition is the cationic fluorinated composition, the secondfluorinated composition typically comprises the particular fluorinatedcopolymer (e.g. the third and/or fourth fluorinated copolymer) in anamount of from 0.01 to 1.50 percent by weight based on the total weightof the cationic fluorinated composition.

After applying the second fluorinated composition to at least onesurface of the sheet, the sheet is typically dried. Drying is carriedout at room temperature or a temperature higher than room temperature,and if necessary, heat treatment may be applied.

In certain preferred embodiments, the first fluorinated composition isthe anionic fluorinated composition and the second fluorinatedcomposition is the cationic fluorinated composition. In theseembodiments, the first fluorinated composition may comprise the firstfluorinated copolymer and/or the second fluorinated copolymer, and thesecond fluorinated composition may comprise the third fluorinatedcopolymer and/or the fourth fluorinated copolymer. Alternatively, thefirst fluorinated composition may comprise an anionic fluorinatedpolymer other than the first and second fluorinated copolymers, and/orthe second fluorinated composition may comprise a cationic fluorinatedpolymer other than the third and fourth fluorinated copolymers.

Typically, in these embodiments, maximum performance of the treatedarticle formed from the method is obtained from utilizing minimalamounts of the fluorinated polymers in the first and second fluorinatedcompositions, respectively. This significantly reduces costs associatedwith preparing treated articles. In addition, despite the amount offluorinated polymers utilized in conventional methods, conventionaltreated articles typically have desirable resistance to creasing yethave undesirable surface performance, or conventional treated articleshave desirable surface performance which suffers considerably when thetreated articles are creased or otherwise bent/deformed. However, themethod prepares treated articles having both excellent surfaceperformance and resistance to creasing. Additionally, the method of thepresent invention utilizes the first and second fluorinatedcompositions, which reduces costs and volume relative to methodsutilizing conventional fluorinated compositions.

It is to be understood that the appended claims are not limited toexpress and particular compounds, compositions, or methods described inthe detailed description, which may vary between particular embodimentswhich fall within the scope of the appended claims. With respect to anyMarkush groups relied upon herein for describing particular features oraspects of various embodiments, it is to be appreciated that different,special, and/or unexpected results may be obtained from each member ofthe respective Markush group independent from all other Markush members.Each member of a Markush group may be relied upon individually and or incombination and provides adequate support for specific embodimentswithin the scope of the appended claims.

It is also to be understood that any ranges and subranges relied upon indescribing various embodiments of the present invention independentlyand collectively fall within the scope of the appended claims, and areunderstood to describe and contemplate all ranges including whole and/orfractional values therein, even if such values are not expressly writtenherein. One of skill in the art readily recognizes that the enumeratedranges and subranges sufficiently describe and enable variousembodiments of the present invention, and such ranges and subranges maybe further delineated into relevant halves, thirds, quarters, fifths,and so on. As just one example, a range “of from 0.1 to 0.9” may befurther delineated into a lower third, i.e., from 0.1 to 0.3, a middlethird, i.e., from 0.4 to 0.6, and an upper third, i.e., from 0.7 to 0.9,which individually and collectively are within the scope of the appendedclaims, and may be relied upon individually and/or collectively andprovide adequate support for specific embodiments within the scope ofthe appended claims. In addition, with respect to the language whichdefines or modifies a range, such as “at least,” “greater than,” “lessthan,” “no more than,” and the like, it is to be understood that suchlanguage includes subranges and/or an upper or lower limit. As anotherexample, a range of “at least 10” inherently includes a subrange of fromat least 10 to 35, a subrange of from at least 10 to 25, a subrange offrom 25 to 35, and so on, and each subrange may be relied uponindividually and/or collectively and provides adequate support forspecific embodiments within the scope of the appended claims. Finally,an individual number within a disclosed range may be relied upon andprovides adequate support for specific embodiments within the scope ofthe appended claims. For example, a range “of from 1 to 9” includesvarious individual integers, such as 3, as well as individual numbersincluding a decimal point (or fraction), such as 4.1, which may berelied upon and provide adequate support for specific embodiments withinthe scope of the appended claims.

The following examples are intended to illustrate the invention and arenot to be viewed in any way as limiting to the scope of the invention.

EXAMPLES Preparation Example 1

Dry sheeted samples of bleached hardwood and softwood sulfate pulps aretorn by hand into pieces (2 inches×3 inches in size). 384 grams of amixture of 60% hardwood and 40% softwood pulps are diluted to 10,000grams in water to form a slurry, and the pulps are left in the slurry tosoak for 48 hours at ambient conditions. The slurry is separated intotwo samples, which each comprise 5,000 grams of the slurry. Each of thesamples is blended for ten seconds to disintegrate the pulps. Thesamples are each diluted to 23 kg to form two diluted mixtures. Thediluted mixtures are refined for 1.5 hours to separate individual fibersof the disintegrated pulps. Both of the diluted mixtures included fibersin an amount of 1.6% by weight based on the dry weight of the fibersrelative to the total weight of the respective diluted mixture.Accordingly, each of the diluted samples were identical such that eitherof the diluted samples may be utilized in the Examples below.

Examples 1-13

Various treated articles are formed in accordance with the method fromthe diluted mixtures, i.e., pulp slurries, formed in Preparation Example1, as described in greater detail below.

In particular, each of the diluted mixtures of Examples 13 is treatedwith a 1% solution of a cationic fix agent (0.05% by weight based on thetotal dry weight of fibers in the diluted mixtures). Then, apre-gelatinized cationic starch is added to each of the diluted mixturesin an amount of 1.00% by weight based on the total dry weight of fibersin the diluted mixtures. A first fluorinated composition which comprisesa first fluorinated copolymer is added to each of the diluted mixtures.The first fluorinated copolymer comprises a cationic fluorinatedcopolymer. The amount of the cationic fluorinated copolymer employed ineach of the first fluorinated compositions is set forth below in Table1.

Each of the diluted mixtures, once the respective first fluorinatedcompositions are combined therewith, is formed into a sheet via acircular TAPPI sheet former (0.02 square meters in area). Each of thesheets has a mass of roughly 60 grams per square meter. Each sheet ispress dried and then contact dried at 110° C. for one minute. Then, asecond fluorinated composition is applied to each of the sheets. Thesecond fluorinated composition comprises a second fluorinated copolymer.The second fluorinated copolymer is the same as the first fluorinatedcopolymer, i.e., the second fluorinated copolymer is also the cationicfluorinated copolymer. The amount of the cationic fluorinated copolymerin each of the second fluorinated compositions is set forth below inTable 1. The second fluorinated compositions are applied to therespective sheets at ambient conditions. Once the second fluorinatedcompositions are applied to the respective sheets, the sheets arecontact dried at 110° C. for one minute to form treated articles.

Mass balances are taken for each sheet to determine the wet coatinguptake of the second fluorinated composition by each sheet. Therespective wet coating uptake values are set forth in Table 1 below.Physical properties of each treated article are measured in accordancewith TAPPI Kit Test T 559 cm-02, entitled “Great resistance test forpaper and paperboard.” The value obtained from the TAPPI Kit Test foreach treated article is set forth below in Table 1. Physical propertiesof each treated article are also measured in accordance with Cobb SizeTest T441 om-09, entitled “Water absorptiveness of sized (non-bibulous)paper, paperboard, and corrugated fiberboard (Cobb test).” The valueobtained from the Cobb test for each treated article is set forth belowin Table 1.

TABLE 1 Wt % First Wt % Second Fluorinated Fluorinated Wet Coating TAPPICobb Trial Copolymer Copolymer Uptake (gsm) Kit Value (gsm) 1 0.4 0.416.65 8.00 23.50 2 0.7 0.1 15.35 5.50 37.00 3 0.4 0.7 16.78 8.67 24.00 40.4 0.4 16.64 8.17 22.00 5 0.4 0.4 16.44 8.50 23.50 6 0.1 0.7 21.1113.00 22.00 7 0.1 0.4 20.8 11.00 22.00 8 0.4 0.1 16.35 5.50 49.50 9 0.40.4 16.45 8.50 23.00 10 0.7 0.4 14.22 6.00 23.00 11 0.7 0.7 14.72 9.1722.00 12 0.1 0.1 21.3 4.00 85.00 13 0.4 0.4 16.1 8.50 24.00

Examples 14-26

Various treated articles are formed in accordance with the method fromthe diluted mixtures, i.e., pulp slurries, formed in Preparation Example1, pursuant to the method describe above relative to Examples 1-13.However, Examples 14-26 differ from Examples 1-13 relative to theparticular first and second fluorinated compositions employed.Specifically, the first fluorinated copolymer of the first fluorinatedcomposition of Examples 14-26 comprises an anionic fluorinatedcopolymer. The second fluorinated copolymer of the second fluorinatedcomposition of Examples 14-26 comprises a cationic fluorinatedcopolymer. The respective amounts of the anionic and cationicfluorinated copolymers employed in the first and second fluorinatedcompositions are set forth below in Table 2.

TABLE 2 Wt % First Wt % Second Fluorinated Fluorinated Wet Coating TAPPICobb Trial Copolymer Copolymer Uptake (gsm) Kit Value (gsm) 14 0.4 0.422.44 8.30 34.00 15 0.7 0.1 15.78 10.00 21.50 16 0.4 0.7 21.61 10.0035.00 17 0.4 0.4 21.72 8.70 34.00 18 0.4 0.4 23.06 8.30 34.50 19 0.1 0.726.65 13.00 31.00 20 0.1 0.4 25.50 10.00 26.00 21 0.4 0.1 22.72 7.0058.00 22 0.4 0.4 21.89 8.50 34.00 23 0.7 0.4 15.28 11.00 26.00 24 0.70.7 15.67 12.00 26.50 25 0.1 0.1 26.80 7.00 33.00 26 0.4 0.4 23.13 8.0035.00

Examples 27-39

Various treated articles are formed in accordance with the method fromthe diluted mixtures, i.e., pulp slurries, formed in Preparation Example1, pursuant to the method describe above relative to Examples 1-13.However, Examples 27-39 differ from Examples 1-13 relative to theparticular first and second fluorinated compositions employed.Specifically, the first fluorinated copolymer of the first fluorinatedcomposition of Examples 27-39 comprises an anionic fluorinatedcopolymer. The second fluorinated copolymer of the second fluorinatedcomposition of Examples 27-39 comprises the same anionic fluorinatedcopolymer as the first fluorinated composition. The respective amountsof the anionic fluorinated copolymers employed in the first and secondfluorinated compositions are set forth below in Table 3.

TABLE 3 Wt % First Wt % Second Fluorinated Fluorinated Wet Coating TAPPITrial Copolymer Copolymer Uptake (gsm) Kit Value 27 0.4 0.4 21.75 6.0028 0.7 0.1 16.75 7.00 29 0.4 0.7 21.25 7.00 30 0.4 0.4 22.75 5.83 31 0.40.4 22.00 6.00 32 0.1 0.7 37.00 12.00 33 0.1 0.4 35.00 10.33 34 0.4 0.121.25 6.00 35 0.4 0.4 22.00 6.00 36 0.7 0.4 16.00 7.00 37 0.7 0.7 15.257.17 38 0.1 0.1 36.00 7.00 39 0.4 0.4 21.00 6.17

The present invention has been described herein in an illustrativemanner, and it is to be understood that the terminology which has beenused is intended to be in the nature of words of description rather thanof limitation. Obviously, many modifications and variations of thepresent invention are possible in light of the above teachings. Theinvention may be practiced otherwise than as specifically describedabove.

What is claimed is:
 1. A method of preparing a treated article, saidmethod comprising the steps of: providing a slurry comprising fibers;combining the slurry and a first fluorinated composition to form amixture; forming at least one sheet from the mixture; and applying asecond fluorinated composition on at least one surface of the at leastone sheet to prepare the treated article; wherein the first fluorinatedcomposition is further defined as a cationic fluorinated compositioncomprising a fluorinated polymer and wherein the second fluorinatedcomposition is further defined as a cationic fluorinated compositioncomprising a fluorinated polymer, and wherein a ratio of the weightpercent of the fluorinated polymer in the first fluorinated compositionto the weight percent of the fluorinated polymer in the secondfluorinated composition is from 1:4 to 1:7.
 2. A method as set forth inclaim 1 wherein the fibers are further defined as cellulosic fibers andthe treated article is further defined as a treated cellulosic article.3. A method as set forth in claim 1 wherein the fluorinated polymer ofthe first and/or second cationic fluorinated composition comprises afirst fluorinated copolymer comprising: (1) a monomer unit based on a(meth)acrylate having a polyfluoroalkyl group; (2) a monomer unit basedon an alkyl(meth)acrylate having a C₁₆-C₁₂ alkyl group; (3) a monomerunit based on an alkyl(meth)acrylate having a C₁-C₂₂ alkyl group; and(4) a monomer unit based on at least one compound selected from thegroup consisting of 2-isocyanate ethyl methacrylate,1,3,3-trimethyl-4-isocyanate cyclohexylmethylamidoxyethyl methacrylateof general formula 1 and 1,3,3-trimethyl-4-isocyanatecyclohexylmethylamidoxyethyl acrylate of general formula 2, theisocyanate group of which is blocked; wherein general formula 1 is

and wherein general formula 2 is


4. A method as set forth in claim 3 wherein the first and/or secondcationic fluorinated composition comprises the first fluorinatedcopolymer in an amount of from 0.01 to 1.50 percent by weight based onthe total weight of the first and/or second cationic fluorinatedcomposition.
 5. A method as set forth in claim 1 wherein the fluorinatedpolymer of the first and/or second cationic fluorinated compositioncomprises a second fluorinated copolymer comprising 60 to 98 mass % ofpolymerized units (d)′ based on monomer (d), from 1 to 20 mass % ofpolymerized units (e)′ based on monomer (e) and from 1 to 30 mass % ofpolymerized units (f)′ based on monomer (f); wherein monomer (d)comprises a compound represented by (Z″—Y″)_(j)X″, wherein Z″ is a C₁₋₆perfluoroalkyl group or a group represented byC_(k)F_(2k+1)O(CFW′CF₂O)_(l)CFK′—, wherein k is an integer of from 1 to6, l is an integer of from 1 to 4, and each of W′ and K′ isindependently a fluorine atom or —CF₃, Y″ is a bivalent organic group ora single bond, j is 1 or 2, and X″ is a polymerizable unsaturated groupprovided that when j is 1, X″ is —CR⁵═CH₂, —COOCR⁵═CH₂, —OCOCR⁵═CH₂,—OCH₂-φ-CR⁵═CH₂ or —OCH═CH₂, and when j is 2, X″ is ═CH(CH₂)_(m)CR⁵═CH₂,═CH(CH₂)_(m)COOCR⁵═CH₂, ═CH(CH₂)_(m)OCOCR⁵═CH₂ or —OCOCH═CHCOO—, whereinR⁵ is a hydrogen atom, a methyl group or a halogen atom, φ is aphenylene group, and m is an integer of from 0 to 4; wherein monomer (e)comprises a compound represented by CH₂═CR⁶-G′-(R⁷O)_(n)—R⁸, wherein R⁶is a hydrogen atom or a methyl group, R⁷ is a C₂₋₄ alkylene group or anotherwise C₂₋₃ alkylene group in which some or all of the hydrogen atomshave been replaced by hydroxyl groups, n is an integer of from 1 to 50,G′ is —COO(CH₂)_(o)— or —COO(CH₂)_(s)—NHCOO—, wherein o is an integer offrom 0 to 4, and s is an integer of from 1 to 4, and R⁸ is at least oneof an acryloyl group and a methacryloyl group; and wherein monomer (f)comprises a compound represented by CH₂═CR⁹-M-Q′-NR¹⁰R¹¹ orCH₂═CR⁹-M-Q′-N(O)R¹⁰R¹¹, wherein R⁹ is a hydrogen atom or a methylgroup, M is —COO— or —CONH—, Q′ is a C₂₋₄ alkylene group or an otherwiseC₂₋₃ alkylene group in which some or all of the hydrogen atoms have beenreplaced by hydroxyl groups, and each of R¹⁰ and R¹¹ comprises a benzylgroup, a C₁₋₈ alkyl group or an otherwise C₂₋₃ alkylene group in whichsome of the hydrogen atoms have been replaced by hydroxyl groups, or R¹⁰and R¹¹ may form a morpholino group, a piperidino group or apyrrolidinyl group, together with a nitrogen atom.
 6. A method as setforth in claim 5 wherein the first and/or second cationic fluorinatedcomposition comprises the second fluorinated copolymer in an amount offrom 0.01 to 1.50 percent by weight based on the total weight of thefirst and/or second cationic fluorinated composition.
 7. A method as setforth in claim 1 wherein the first fluorinated composition furthercomprises water and a water-soluble solvent selected from the group ofpropylene glycol, dipropylene glycol, tripropylene glycol, propyleneglycol monomethyl ether, propylene glycol monoethyl ether, glycolmonomethyl ether, dipropylene glycol monoethyl ether, tripropyleneglycol monomethyl ether, and combinations thereof.
 8. A method as setforth in claim 1 wherein the second fluorinated composition furthercomprises water and a water-soluble solvent selected from the group ofpropylene glycol, dipropylene glycol, tripropylene glycol, propyleneglycol monomethyl ether, propylene glycol monoethyl ether, dipropyleneglycol monomethyl ether, dipropylene glycol monoethyl ether,tripropylene glycol monomethyl ether, and combinations thereof.
 9. Amethod as set forth in claim 1 wherein the first fluorinated compositionand the second fluorinated composition each independently furthercomprise a starch.
 10. A method as set forth in claim 1 wherein the stepof applying the second fluorinated composition on at least one surfaceof the at least one sheet comprises applying the second fluorinatedcomposition by spraying, brushing, padding, size press coating, meteringsize press coating, film press coating, gravure coating, flexo coating,roller coating, rotor dampening, foaming, gate roll coating, bill bladecoating, bar coating, intaglio coating, reverse roll coating, skid rollcoating, transfer (offset) roll coating, knife coating, knife-over-rollcoating, J-coating, air knife coating, curtain coating, and combinationsthereof.
 11. A method as set forth in claim 1 further comprising thestep of refining the fibers by subjecting the fibers to a shear force.12. A method as set forth in claim 1 further comprising the step ofdrying the sheet prior to the step of applying the second fluorinatedcomposition on at least one surface of the sheet.
 13. A method as setforth in claim 1 wherein the step of applying the second fluorinatedcomposition comprises applying the second fluorinated composition on allmajor surfaces of the at least one sheet.
 14. A method as set forth inclaim 1 further comprising the step of drying the sheet after the stepof applying the second fluorinated composition on at least one surfaceof the sheet.
 15. A method of preparing a treated article, said methodcomprising the steps of: providing a slurry comprising fibers; combiningthe slurry and a first fluorinated composition to form a mixture;forming at least one sheet from the mixture; and applying a secondfluorinated composition on at least one surface of the at least onesheet to prepare the treated article; wherein the first fluorinatedcomposition is further defined as a cationic fluorinated compositioncomprising from 0.1 to 0.7 wt. % of a first fluorinated copolymer, andwherein the second fluorinated composition is further defined as acationic fluorinated composition comprising from 0.1 to 0.7 wt. % of asecond fluorinated copolymer, wherein a ratio of the wt. % of thefluorinated copolymer in the first fluorinated composition to the wt. %of the fluorinated copolymer in the second fluorinated composition isfrom 1:4 to 1:7.
 16. A treated article formed in accordance with themethod of claim
 15. 17. A treated sheet of paper formed in accordancewith the method of claim
 15. 18. A method of preparing a treatedcellulosic article, said method comprising the steps of: providing aslurry comprising cellulosic fibers; combining the slurry and a firstfluorinated composition to form a mixture; forming at least one sheetfrom the mixture; and applying a second fluorinated composition on atleast one surface of the at least one sheet to prepare the treatedcellulosic article; wherein the first fluorinated composition is furtherdefined as a cationic fluorinated composition comprising a fluorinatedpolymer and wherein the second fluorinated composition is furtherdefined as a cationic fluorinated composition comprising a fluorinatedpolymer wherein a ratio of the wt. % percent of the fluorinated polymerin the first fluorinated composition to the wt. % of the fluorinatedpolymer in the second fluorinated composition is from 1:4 to 1:7.